Reed relay having preliminarily operating contacts



United States Patent 3,289,128 REED RELAY HAVTNG PRELMVIEJARILY OPERATING CONTAQTS Robert K. Else, Glen Ellyn, llL, assiguor to Automatic Electric Laboratories, 111e,, Northlake, 11]., a corporation of Delaware Filed Oct. 14, 1965, Ser. No. 495,838 8 Claims. (Cl. 335-152) This invention relates to reed relays and also to line circuit arrangements for telephone, and the like, systems, in which these relays may be used advantageously.

The reed relays of the prior art are generally of the type having individual make and/or break contacts which are operated upon the energization of the coil wound about the relay bobbin.

The instant invention provides a reed relay not only having the usual make and/or break contacts, but one having in addition, preliminarily operating contacts. In this manner, combinations of functions that, in the past, have been attainable only with relays, such as telephone relays, of the armature and spring pile-up type, are made available for individual reed-type relays.

Accordingly, it is an object of this invention to provide a reed relay having make and/ or break, and preliminarily operating contacts.

Still another object of this invention is to provide a reed relay which can be used in telephone, or the like, systems to perform both the line and cut-off functions for which in the prior art two individual reed relays were required.

The above and other objects and the features of the invention will become more apparent from a further perusal of the following detailed description of a preferred embodiment of the invention, taken in conjunction with the accompanying drawings.

This embodiment, which has practical application, for example, as a combination line and cut-off reed relay in telephone, or the like, systems, comprises three windings wound on a solid core, L-shaped flux concentrators on each end of the core which direct the flux in the proper magnitude to reed switches which are located on the periphery of the coil assembly, and a permanent magnet. Two of the reed switches are adjacent the permanent magnet and act as normally closed contacts. Another of the reed switches is positioned close to the flux concentrators so as to operate as a preliminary make contact upon energization of two of the three windings. The remaining reed switch, which is located at a greater distance from the flux concentrators, operates, along with the two normally closed contact reed switches, upon energization of the third winding whose flux aids windings one and two.

FIG. 1 is a top view of the reed relay according to the invention.

FIG. 2 is a side View of the reed relay of FIG. 1.

FIG. 3 is a front view of the reed relay of FIG. 1.

FIG. 4 is a schematic diagram incorporating the reed relay according to the invention for use as a combination line and cut-off relay.

FIGS. 1-, 2 and 3 show relay comprising coil wound bobbin 24 having a solid magnetic iron core 40. Attached by means of screws 23 to core 40 are flux concentrators 22. Located on the periphery of bobbin 24 are reed switches 25, 26, 27 and 28. Magnet 21 located adjacent reed switches 26 and 27 serves to keep these particular switches in a normally closed position. Reed switch 28 is located adjacent the legs of flux concentrators 22, and thereby function as .a preliminary make contact as will be shown in greater detail hereafter.

3,289,128 Patented Nov. 29, 1966 FIG. 4 illustrates how a reed relay according to the invention can be advantageously used as a combination line and cut-cit relay in a line circuit. By way of example, FIG. 4 shows the line circuit LC111 including reed relay 9 as part of an electronic telephone switching system of the general type disclosed in co-pending application, Marker For A Communication Switching Network, W. R. Wedmore, Serial No. 304,892, filed August 27, 1963, assigned to the same assignee. Attention is particularly directed to FIG. 12 of the above-mentioned application.

As can be seen from FIG. 4, windings 1 and 2 of relay 9 are connected through break contacts 41 and 42, respectively (which correspond to contacts 1 and 2 of relay 12CO shown in FIG. 12 in the copending application), to subscriber line leads L111R and L111T which are in turn connected to subscriber station S111. Battery 37 is supplied through winding 2 of relay 9 and ground 38 is supplied through winding 1 of relay 9. Control lead LlllC is connected through winding 3 of relay 9 to battery 47, and pull lead L111P is connected to resistance-battery 13 through preliminary make contacts 44. (These contacts correspond to contacts 1 of relay 12L in FIG. 12 of the copending application, in FIG. 12, however, resistance battery is supplied ove-r lead LRl.) Pull lead L111P, furthermore, is connected to ground 14 through make contacts 43. (These last-mentioned contacts correspond to contacts 3 of relay 12CO in FIG. 12 of the copending application, in FIG. 12, ground is supplied over lead BCO.)

Leads L111T, L111R, L111C, and L111P are in turn connected through matrices 45, through originating junctor 46 and in turn to register sender 48. These components all have their obvious counterparts in the disclosure of the copending application.

The detailed operation of the reed relay according to the invention is as follows:

Looking at FIGS. 1, 2 and 3 when two of the three windings wound about bobbin 24 are energized, reed switch contact pair 28, which is located adjacent flux concentrators 22, will operate. The energization of the two windings produces a magnetic field which is in opposition to the magnetic field produced by permanent magnet 21 used to hold reed switches 26 and 27 in a normally closed position, but is not strong enough to overcome the field of the permanent magnet. It is also not of sulficient strength to operate normally open reed switch 25 which has no flux concentrators in close proximity to it. As winding 3 is energized, reed switches 25, 26 and 27 operate, that is, reed switch 25 closes and reed switches 26 :and 27 open. Winding 3 is energized in a direction so as to create a magnetic field which aids the magnetic field produced by windings 1 and 2. This field, by itself as well as in combination with the previously mentioned field, is sulficient to operate reed switches 25, 26 and 27.

A detailed description of the operation of relay 9 as shown in FIG. 4, where it is used as a combined line and cut-off relay, will now be given.

Assuming first that a telephone call is originated at substation S111, it will be clear that when the handset of substation S111 is in the off-hook position, a loop circuit comprising ground 38, winding I, normally closed reed switch contact pair 41, line lead L111T, substation S111, line lead L111R, normally closed reed switch contact pair 42, winding 2, and battery 37, is completed. The completion of this circuit energizes windings 1 and 2 of relay 9. The flux produced by the energization of these windings is sufficient to close preliminary make contacts 44, which places resistance-battery 13 on pull lead L111P, but it is not sufficient to actuate any of contacts 41, 42 or 43.

Resistance-battery 13 is then detected by originating junctor 46 through the windings of certain crosspoint relays in matrices 45. Originating junctor 46, which contains identifying matrices, identifies the calling line and causes the closing of certain contacts of the crosspoint relays in matrices 45 to provide a path for leads L111T, L111R and L111C through to the register sender, all as described in detail in the copending application. Register sender 48 then operates to have a ground sent back through originating junctor 46, over the reed switch crosspoint contact path through matrices 45, over control lead L111C to winding 3 of relay 9. This energizes winding 3 in flux aiding with the windings 1 and 2. The flux produced by winding 3 itself being suflicient to cause contact pairs 41 and 42 to open and contact pair 43 to close. The opening of contacts 41, 42 removes the line portion of relay 9 (e.g., windings 1 and 2) from line leads L111T, L111R to clear the line conductors from attachments, thereby to facilitate pulsing to register sender 48. Contact pair 43 in closing places ground 14 on pull lead LlllP, marking the line busy.

Likewise, when substation S111, shown in FIG. 4, is accessed as a termination point the operation of relay 9 is facilitated over control lead L111C from a terminating junctor (not shown), to operate as a cut-off relay with all its incidental functions.

A more detailed operation of the electronic switching system of which relay 9 is made a part in FIG. 4, may be had by referring to the aforementioned copending patent application. However, the relay according to the invention may be adapted to be used with other types of telephone systems.

It will be obvious to those skilled in the art that changes and modifications may be made without departing from this invention in its broadest aspects, and therefore the aim in the appended claims is to cover'all such changes and modifications as in the true spirit and scope of this invention.

What is claimed is:

1. A reed relay comprising:

first, second, and third pairs of magnetically actuable reed contacts;

electromagnetic winding means for actuating said three pairs;

said first and second pairs of reed contacts being normally open;

a permanent magnet adjacent said third reed contact pair to hold said pair normally closed;

and means for rendering said first reed contact pair more sensitive to the magnetic field produced by said winding means than said second contact pair so that upon a relatively low-level energization of said winding means, a flux is produced which is sufiicient only to close said first, normally open, contact pair, whereas only upon a relatively high-level energization of said winding means, a flux is produced which is suflicient to also close said second, normally open, contact pair, said last-mentioned flux also being of sufficient magnitude to overcome said permanent magnet so as to open said third, normally closed, contact pair.

2. A reed relay comprising:

first, second and third pairs of magnetically actuable reed contacts,

said first and second pairs being normally open,

a magnetic iron core having electromagnetic winding means wound thereabout,

a permanent magnet adjacent said third reed contact pair to hold said pair normally closed,

and a pair of flux concentrators each connected to an end of said core and having a leg thereof extending adjacent said first contact pair only, for rendering said first reed contact pair more sensitive to the magnetic field produced by said winding means than said second contact pair, so that upon a relatively low-level energization of said winding means, a flux is produced which is sufficient only to close said first, normally open, contact pair, whereas only upon a relatively high-level energization of said winding means, a flux is produced which is sufiicient to also close said second, normally open contact pair, said last-mentioned flux also being of suflicient magnitude to overcome said permanent magnet so as to open said third, normally closed, contact pair.

3. A reed relay comprising:

a core made of magnetic iron material;

first and second winding means wound about said core;

a plurality of reed switches disposed parallel to and generally peripherally about said core, each reed switch having a pair of contacts therein;

a first and second of said reed switches having normally open contacts;

a permanent magnet located adjacent a third of said reed switches to hold the contact pair therein normally closed;

a pair of L-shaped flux concentrators each connected to an end of said core and having a leg thereof extending adjacent said first reed switch for rendering said first reed switch contact pair more sensitive to the magnetic field produced by said windings than said second reed switch contact pair, so that upon the energization of said first winding means, said first, normally open reed switch contact pair closes, whereas upon energization of said second winding means, said second, normally open, reed switch contact pair closes in addition to said first pair, and said third, normally closed, reed switch contact pair opens.

4. In combination:

a reed relay comprising first, second, third and fourth pairs of magnetically actuable reed contacts;

said first and second pairs being normally open,

first, second and third windings;

a permanent magnet adjacent said third and fourth reed contact pairs to hold said pairs normally closed;

and means for rendering said first reed contact pair more sensitive to the magnetic field produced by said windings than said second contact pair;

a first circuit including said first and second windings,

and said third and fourth, normally closed, reed contact pairs in series, said first and second windings being energized upon completion of said circuit to close said first and reed contact pair,

and a second circuit including said third winding, said circuit being prepared by the closure of said first contact pair and said third winding being energized upon completion of said second circuit to close said second, normally open, reed contact pair and open said third and fourth, normally closed, reed contact pairs thereby disconnecting said first and second windings from said first circuit, said first and second pairs being held closed and said third and fourth pairs open due to the energization of said third winding.

5. In combination:

a reed relay comprising first, second, third and fourth reed switches each having a pair of contacts therein;

said first and second reed switches being normally open;

a magnetic iron core having first, secondand third windings wound thereabout;

a permanent magnet adjacent said third and fourth reed switches to hold said reed switches normally closed;

and a pair of L-shaped flux concentrators each connected to an end of said core and having a leg thereof extending adjacent said first reed switch only, rendering said contact pair therein more sensitive to the magnetic field produced by said windings for preliminary operation of said first reed switch;

a first circuit including said first and second windings and said third and fourth, normally closed, reed switches in series, said first and second windings being energized upon completion of said circuit to close said first reed switch contact pair;

and a second circuit including said third winding;

said circuit being prepared by the closure of said first reed switch contact pair and said third winding being energized upon completion of said second circuit to close said second, normally open, reed switch contact pair and to open said third and fourth, normally closed, reed switch contact pairs thereby disconnecting said first and second windings from said first circuit;

said first and second pairs being held closed and said third and fourth pairs open due to the energization of said third winding.

6. A line circuit arrangement comprising in combinationa combined line and cut-oif relay of the reed relay type having line winding means and cut-off winding means and having first, second and third reed switches each with a pair of contacts, said first and second reed switch contacts pairs being normally open,

a permanent magnet adjacent said third reed switch to hold its contact pair normally closed,

means for rendering said first reed contact pair more sensitive to the magnetic field produced by said winding means than said second contact pair,

a loop circuit including said line winding means and said third, normally closed, reed switch in series, said line winding means being energized upon completion of said loop circuit to close said first reed switch contact pair;

and a cut-off circuit including said cut-off winding means, said cut-01f circuit being prepared by the closure of said first reed switch and said cut-oft winding means being energized upon completion of said cut-off circuit to close said second, normally open, reed switch contact pair and open said third, normally closed, reed switch contact pair thereby disconnecting said line winding means from said loop circuit,

said first and second reed switch contact pairs being held closed and said third reed switch contact pair open due to the energization of said cut-off winding means.

7. A combined line and cut-off relay arrangement,

comprising in combination:

a reed relay comprising first, second, third and fourth reed switches each having a pair of contacts therein;

said first and second reed switch contact pairs being normally open;

a magnetic iron core having line winding means and cut-off winding means Wound therea-bout;

a permanent magnet adjacent said third and fourth reed switches to hold the contact pairs therein normally closed;

and a pair of L-shaped flux concentrators each connected to an end of said core and having a leg thereof extending adjacent said first reed switch for rendering said contact pair therein more sensitive to the magnetic field produced by said winding means than said second normally open, reed switch contact pair;

a loop circuit including said line winding means and said third and fourth, normally closed, reed switches in series, said line winding means being energized upon completion of said loop circuit to close said first reed switch contact pair;

and a cut-off circuit including said cut-off winding means, said cut-off circuit being prepared by the closure of said first reed switch and said cut-off winding means being energized upon completion of said cut-oif circuit to close said second, normally open, reed switch contact pair and open said third and fourth, normally closed, reed switch contact pair thereby disconnecting said line winding means from said loop circuit;

said first and second reed switch contact pairs being held closed and said third and fourth reed switch contact pairs open due to the energization of said cutoff winding means.

8. A line circuit arrangement comprising in combination a combined line and cut-off relay of the reed relay type having line winding means and cut-off winding means and having first and second reed switches each with a pair of contacts, said first contact pair being normally open, and said second contact pair being normally closed,

means for rendering said first reed contact pair more sensitive to the magnetic field produced by said winding means than said second contact pair,

a loop circuit including said line winding means and said second, normally closed, contact pair in series,

1 said line Winding means being energized upon completion of said loop circuit to actuate said first, normally open, contact pair only,

and a cut-off circuit including said cut-off winding means, said cutoif circuit being prepared by the closure of said first contact pair and said cut-off winding means being energized upon completion of said cut-otf circuit to additionally actuate said second, normally closed, contact pair thereby disconnecting said line winding means from said loop circuit.

References Cited by the Examiner UNITED STATES PATENTS BERNARD A. GILHEANY, Primary Examiner.

J. BAKER,

Assistant Examiner. 

1. A REED RELAY COMPRISING: FIRST, SECOND, AND THIRD PAIRS OF MAGNETICALLY ACTUABLE REED CONTACTS; ELECTROMAGNETIC WINDING MEANS FOR ACTUATING SAID THREE PAIRS; SAID FIRST AND SECOND PAIRS OF REED CONTACTS BEING NORMALLY OPEN; A PERMANENT MAGNET ADJACENT SAID THIRD REED CONTACT PAIR TO HOLD SAID PAIR NORMALLY CLOSED; AND MEANS FOR RENDERING SAID FIRST REED CONTACT PAIR MORE SENSITIVE TO THE MAGNETIC FIELD PRODUCED BY SAID WINDING MEANS THAN SAID SECOND CONTACT PAIR SO THAT UPON A RELATIVELY LOW-LEVEL ENERGIZATION OF SAID WINDING MEANS, A FLUX IS PRODUCED WHICH IS SUFFICIENT ONLY TO CLOSE SAID FIRST, NORMALLY OPEN, CONTACT PAIR, WHEREAS ONLY UPON A RELATIVELY HIGH-LEVEL ENERGIZATION OF SAID WINDING MEANS, A FLUX IS PRODUCED WHICH IS SUFFICIENT TO ALSO CLOSE SAID SECOND, NORMALLY OPEN, CONTACT PAIR, SAID LAST-MENTIONED FLUX ALSO BEING OF SUFFICIENT MAGNITUDE TO OVERCOME SAID PERMANENT MAGNET SO AS TO OPEN SAID THIRD, NORMALLY CLOSED, CONTACT PAIR. 